.formal{
    width:990px;
    margin:0 auto;
    text-align: center;
    letter-spacing: 0.1em;
}
.formal_pic li{
    float:left;
    padding:0 10px;
    margin:30px 0;
}
.formal_pic li img{
    width:475px;
}
.main_hover{
    position: absolute;
    left:10px;
    top:0;
    opacity: 0;
}
.main_hover p{
    position: absolute;
    left:43%;
    bottom:38%;
    color:#fff;
    font-size: 16px;
}
.main li:hover{
    transform:translate(0,-5px);
    transition:all 0.5s;
}
.main li:hover .main_hover{
    transition: all 0.5s;
    opacity: 1;
    box-shadow:#ddd 0 0 3px 5px;
}